CN201222055Y - Apparatus for measuring ultrasonic gas concentration - Google Patents
Apparatus for measuring ultrasonic gas concentration Download PDFInfo
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- CN201222055Y CN201222055Y CNU2008200635194U CN200820063519U CN201222055Y CN 201222055 Y CN201222055 Y CN 201222055Y CN U2008200635194 U CNU2008200635194 U CN U2008200635194U CN 200820063519 U CN200820063519 U CN 200820063519U CN 201222055 Y CN201222055 Y CN 201222055Y
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Abstract
The utility mode relates to an ultrasonic gas measuring device adaptable to changes of temperature, which mainly includes a master control circuit board and a measuring chamber. The master control circuit board includes a single-chip microcomputer, a temperature signal sampling circuit and a waveform conditioning circuit, while the measuring chamber includes an outer cylinder, a gas inlet screen, a gas outlet screen, an O-shaped rubber ring, an elastic retaining ring, a sound absorber, a transmitting board, a receiving board, thermistors, an ultrasonic emitter, and an ultrasonic receiver, wherein one thermistor mounted at the gas inlet screen is used for measuring the change trend of the measured gas, the other thermistor located inside an eccentric small through-hole of the sound absorber is used for measuring the temperature of the measured gas, and accurate temperature compensation is realized by the two thermistors functioning variably, thereby increasing the measuring accuracy.
Description
Affiliated technical field
The utility model relates to a kind of ultrasonic gas apparatus for measuring concentration, can be in two component gases environment measure gas concentrations.
Background technology
When ultrasound wave is propagated in two component gases, transmit and received signal between have phase differential, phase differential is with the linear inverse relation of the fast gas concentration of velocity of wave, with the linear proportional relation of the slow gas concentration of velocity of wave.Change owing to ultrasonic velocity varies with temperature, therefore, need take the temperature compensation measure, could eliminate the measuring error that temperature variation is brought.Existing temperature compensation measure has certain limitation, because during measure gas concentrations, to in an airtight test chamber structure, carry out, common way is in inside cavity a temperature sensor only to be installed, this temperature sensor is placed on any position of inside cavity, the capital is when the gas temperature acute variation, and it is leading or lag behind actual temperature value to cause measuring temperature value, thereby brings bigger measuring error.
Summary of the invention
For overcoming the improper big measuring error that causes of temperature compensation, the utility model provides a kind of ultrasonic gas apparatus for measuring concentration, this device has improved promptness, the accuracy of temperature compensation, can adapt to all temps situation of change, thus accurate measure gas concentrations.
The technical scheme that its technical matters that solves the utility model adopts is: by the ultrasonic gas apparatus for measuring concentration that main control board and test chamber are formed, its main control board is by single-chip microcomputer, the temperature signal sample circuit, the waveform finishing circuit is formed, its test chamber is by urceolus, air inlet baffle plate, the baffle plate of giving vent to anger, O type rubber ring, circlip, acoustic(al)absorbent, expelling plate, dash receiver, thermistor, ultrasonic emitting head, ultrasound wave receive head and form, wherein, acoustic(al)absorbent is positioned at the inner stage casing of urceolus, and a thermistor is positioned at air inlet baffle plate place, is used for measurement gas variation of temperature trend, a thermistor is positioned at acoustic(al)absorbent inside, is used for the measurement gas temperature.
Single-chip microcomputer by the I/O port respectively with the ultrasonic emitting head, the temperature signal sample circuit, the waveform finishing circuit connects, the single-chip microcomputer plug-in produces the square-wave signal of a string fixed frequency, offer the ultrasonic emitting head by the I/O port, ultrasound wave receives a same waveform finishing circuit and connects, this circuit is made up of comparer and peripheral resistance topological network thereof, can convert the ultrasonic signal that receives to square-wave signal, and be read into the internal dynamic storer by the single-chip processor i/o port, the temperature signal sample circuit that two thermistors constitute with two resistance topological networks respectively, with temperature transition is voltage signal, be read into the internal dynamic storer by the single-chip processor i/o port, single-chip microcomputer is according to the phase differential of measuring, temperature variation, and according to different temperature variations, adopt different temperature compensation values, computing formula by setting in advance calculates gas concentration.
Urceolus is the hollow circuit cylinder body structure, adopts engineering plastics, and its inside is that the stage casing internal diameter is little, the axially extending bore that the both sides internal diameter is big, and the joint portion of both sides endoporus and stage casing endoporus is an annular platform, the both sides inwall respectively has a circlip groove.
Acoustic(al)absorbent is the cylindrical structure that two axially extending bores are arranged, the foam sponge of density in the employing, its length, external diameter and urceolus stage casing through hole length, diameter are consistent, the central through hole diameter is with the maximum profile diameter unanimity of ultrasonic emitting head, reception head, eccentric part has another small through hole, and the aperture is with thermistor diameter unanimity.
The main body of expelling plate, dash receiver is a circular circuit board, diameter is consistent with the through-hole diameter of urceolus both sides, the plate upper edge is slightly less than the circumference of acoustic(al)absorbent external diameter, be evenly distributed with several small through hole, be close to circular circuit board center welding ultrasonic emitting head and receive head, receive thermistor of head next door welding, four metal needles are welded at the back side again; Thermistor of center, emitting head back side welding, four metal needles are welded on the next door again, and two groups of metal needles receive head, thermistor electrical connection with emitting head respectively by circular circuit board Copper Foil cabling.
The air inlet baffle plate is identical with the baffle arrangement of giving vent to anger, adopt engineering plastics, its axis has a through hole, the first half be can the overcoat tracheae valve, Lower Half is the circular bottom plate that diameter equals urceolus both sides through-hole diameter, even four apertures that distribute of straight line above the base plate, and pitch-row equals four pin metal stitch spacings, the aperture is slightly larger than the metal needle diameter, can allow metal needle pass aperture.
Acoustic(al)absorbent is installed in urceolus central through hole inside, radiating circuit plate and circuit board for receiving are installed in both sides, ultrasonic emitting head and reception head just in time extend into acoustic(al)absorbent central through hole the inside, and the thermistor on the circuit board for receiving just in time extend into the eccentric small through hole of acoustic(al)absorbent centre position, and the thermistor on the radiating circuit plate just in time extend into the through hole centre position of air inlet baffle plate.
Expelling plate and dash receiver both sides are installed O type rubber ring respectively, the air inlet baffle plate, the baffle plate of giving vent to anger, circlip, and metal needle is curved 90 degree angles after passing aperture on the inlet, outlet plate baffle plate, circlip is stuck in the circlip groove of outer tube inner wall, can keep off the baffle plate of compressing into, give vent to anger, and then compression O type rubber ring, rely on O type rubber ring elastic force expelling plate, dash receiver to be squeezed on the ring-shaped platform of urceolus inside, and metal needle is welded on the main control board, make test chamber and main control board realize being electrically connected and fixedly becoming one.
The beneficial effects of the utility model are, when utilizing the two component gases concentration of ultrasonic measurement, can adapt to all temps situation of change, accurately measure gas concentrations, test chamber is simple in structure, assembling easily, volume is little, and is in light weight, the governor circuit board component is few, circuit is simple and clear, and test chamber not only realized electrical connection with main control board by eight metal needles, has also realized fixedly connected.
Description of drawings
Below in conjunction with drawings and Examples the utility model is further specified.
Fig. 1 is a schematic block circuit diagram of the present utility model.
Fig. 2 is test chamber principles of construction figure of the present utility model
Fig. 3 is the complete machine outside drawing of an embodiment.
Fig. 4 is the vertical assembling section of the test chamber of an embodiment.
Fig. 5 is the circuit diagram of an embodiment.
Fig. 6 is the phase differential oscillogram of the oxygen concentration correspondence of an embodiment.
Fig. 7 is the phase differential curve map of the oxygen concentration correspondence of an embodiment.
Fig. 8 is the curve map of the oxygen concentration corresponding temperature under two kinds of temperature compensation modes of an embodiment.
Among the figure, M1. test chamber, M2. main control board, 1. urceolus, 2. acoustic(al)absorbent, 3. circular circuit board, 4. circular circuit board, 5.O type rubber ring, 6.O type rubber ring, 7. air inlet baffle plate, 8. give vent to anger baffle plate, 9. circlip, 10. circlip, 11. 4 metal needles, 12. 4 metal needles, 13. fluid sealant, 14. fluid sealants, RT1. thermistor, RT2. thermistor, S1. ultrasonic emitting head, the S2. ultrasound wave receives head, U1. single-chip microcomputer, U2. temperature signal sample circuit, U3. waveform finishing circuit, U4. sound light alarming circuit, U31. comparer.
Embodiment
Among Fig. 4, ultrasonic emitting head (S1) is welded on the center of circular circuit board (3), ultrasound wave receives the center that head (S2) is welded on circular circuit board (4), thermistor (RT1) is welded on the center at circular circuit board (3) back side, keep vertical with circular circuit board (3), highly be controlled at half position of air inlet baffle plate (7) height, four metal needles (11) are vertically welded in thermistor (RT1) homonymy relative position, thermistor (RT2) is welded on the position that ultrasound wave receives head (S2) homonymy next door, keep vertical with circular circuit board (4), highly be controlled at half of acoustic(al)absorbent (2) length, four metal needles (12) are vertically welded in thermistor (RT2) back side relative position.O type rubber ring (5) is consistent with O type rubber ring (6) specifications and models, and air inlet baffle plate (7) is consistent with the baffle plate of giving vent to anger (8) physical dimension, and circlip (9) is consistent with circlip (10) specifications and models.Thermistor (RT1) is consistent with thermistor (RT2) specifications and models.When assembling air inlet baffle plate (7) and the baffle plate of giving vent to anger (8), four metal needles (11) and four metal needles (12) should be passed air inlet baffle plate (7) and the top small through hole of the baffle plate of giving vent to anger (8), then four metal needles (11) and four metal needles (12) are curved an angle of 90 degrees respectively, assemble circlip (9) and circlip (10) more respectively.Use fluid sealant (13) and fluid sealant (14) to seal, guarantee that test chamber (M1) is air tight, and four metal needles (11) and four metal needles (12) are welded on respectively on the main control board (M2), realize the electrical connection of test chamber (M1) and main control board (M2), and test chamber (M1) is fixed on the main control board (M2).
Among Fig. 5, single-chip microcomputer (U1) is connected with temperature signal sample circuit (U2), waveform finishing circuit (U3), sound light alarming circuit (U4) by its I/O port.Single-chip microcomputer (U1) sends the continuous square wave of a string 40KHZ by the IN1 port and gives ultrasonic emitting head (S1), ultrasound wave receives head (S2) and receives a string 40KHZ sine wave, through the waveform finishing circuit of forming by comparer (U31) and peripheral resistor network (U3), export a string continuous 40KHZ square wave, read in by single-chip microcomputer (U1) IN2 port, simultaneously, single-chip microcomputer (U1) passes through IN3, the IN4 port, the partial pressure value of thermistor (RT1) and thermistor (RT2) resistance correspondence is read in the interior A/D of sheet of single-chip microcomputer (U1), convert numerical value to, being tabled look-up by program to obtain corresponding temperature.Single-chip microcomputer (U1) plug-in can be set high and low two concentration alarm set points, by the light emitting diode of three kinds of colors in the sound light alarming circuit (U4), embodies high, medium and low three kinds of CONCENTRATION STATE, when being lower than alarm set point, and the conducting buzzer warning.
Among Fig. 6, Fig. 7, when measuring at the oxygen concentration in the two component gases of oxygen nitrogen, after the IN1 port of single-chip microcomputer (U1) sends square wave TS1, single-chip microcomputer (U1) internal counter begins counting at the TS1 rising edge, when the IN2 port of single-chip microcomputer (U1) receives first rising edge of square wave G1, G2, G3, counter stops counting, and this gate time is exactly phase differential (time difference).If G2 is the concentration value of known high-concentration oxygen, produce phase differential dt2, corresponding temperature is tm0, G1 is a known low concentrations concentration of oxygen value, produces phase differential dt1, and corresponding temperature also is tm0, because the nitrogen velocity of wave is faster than the oxysome velocity of wave, so the linear proportional relation of oxygen density value and phase differential is because two kinds of oxygen density values are known, with concentration difference G2-G1, divided by phase differential difference dt2-dt1, just can obtain the ratio of oxygen concentration and phase differential, when unknown oxygen concentration G3 produces phase differential dt3, when corresponding temperature is tm3, deduct dt1 by dt3, multiply by this ratio again, add G1 at last, just can calculate the concentration value of unknown oxygen G3.Simultaneously, if temperature t m3 equals temperature t m0, calculating the gained concentration value need not revise, if temperature t m3 is not equal to temperature t m0, needing to introduce temperature compensation value revises, revise this moment in two kinds of situation: the temperature difference between thermistor (RT1) and thermistor (RT2) hour shows that temperature variation is less, adopts offset rate to participate in compensating; When the temperature difference between thermistor (RT1) and the thermistor (RT2) is big, show that temperature variation is violent, adopt another offset rate1 to participate in compensation, the rate1 value is bigger than the rate value, plays the acceleration compensating action.Single-chip microcomputer (U1) can deposit in the value of G2, G1, tm0, rate, rate1 among the EEPROM respectively, phase differential and two temperature values according to real-time measurement, and call G2, G1, tm0, rate, rate1 value among the EEPROM, calculate different oxygen density values.
Among Fig. 8, the two component gases concentration of the oxygen nitrogen of concentration known are constant, and oxygen density value is MO2, when changing temperature, use two kinds of temperature compensations to measure, a kind of be single-chip microcomputer (U1) plug-in according to the temperature variations between thermistor (RT1) and the thermistor (RT2), carry out logic determines, in the C1 interval of temperature-resistant or slow variation, use rate to compensate, in the C2 interval of temperature acute variation, use rate1 to compensate, the oxygen density value curve of calculating is K1; Another kind is the temperature value that single-chip microcomputer (U1) plug-in is only monitored thermistor (RT2), does not monitor the temperature value of thermistor (RT1), and only uses rate to compensate, and the oxygen density value curve that calculates gained is K2.The temperature curve that on behalf of thermistor (RT2), the temperature curve that on behalf of thermistor (RT1), T1 record, T2 record.In the C1 interval, K1, K2 than the error of MO2 all less than 1.5%; In the C2 interval, T1 and T2 form price scissors in the temperature fast rise stage, and less than 2.0%, and K2 surpasses 10% than the error of MO2 is maximum to K1 than the error of MO2.Find out thus, different situations of change according to temperature, utilize thermistor (RT1) characteristics of response fast, and according to corresponding logic judging function, be used alternatingly rate and rate1 compensates, the slow situation of change of adaptive temperature not only can also adaptive temperature acute variation situation, realize temperature compensation accurately, thereby improve accuracy of measurement.
Claims (8)
1. supersonic gas fluid measurement device, main control board and test chamber are electrically connected, and it is characterized in that: main control board is by single-chip microcomputer, the temperature signal sample circuit, the waveform finishing circuit is formed, test chamber is by urceolus, air inlet baffle plate, the baffle plate of giving vent to anger, O type rubber ring, circlip, acoustic(al)absorbent, expelling plate, dash receiver, thermistor, ultrasonic emitting head, ultrasound wave receive head and form, wherein, acoustic(al)absorbent is positioned at the inner stage casing of urceolus, and a thermistor is positioned at air inlet baffle plate place, and a thermistor is positioned at acoustic(al)absorbent inside.
2. supersonic gas fluid measurement device according to claim 1, it is characterized in that: single-chip microcomputer is electrically connected with ultrasonic emitting head, temperature signal sample circuit, waveform finishing circuit respectively by the I/O port, the waveform finishing circuit is made up of comparer and peripheral resistance topological network thereof, receive head with ultrasound wave and be electrically connected, two thermistors constitute the temperature signal sample circuit with two resistance topological networks respectively.
3. supersonic gas fluid measurement device according to claim 1, it is characterized in that: urceolus is the engineering plastics of hollow circuit cylinder body structure, its inside is that the stage casing internal diameter is little, the axially extending bore that the both sides internal diameter is big, the joint portion of both sides endoporus and stage casing endoporus is an annular platform, and the both sides inwall respectively has a circlip groove.
4. supersonic gas fluid measurement device according to claim 1, it is characterized in that: acoustic(al)absorbent is the cylindrical structure that two axially extending bores are arranged, material is the polyurethane foam sponge of middle density, its length, external diameter and urceolus stage casing through hole length, diameter are consistent, the central through hole diameter is with the maximum profile diameter unanimity of ultrasonic emitting head, reception head, eccentric part has another small through hole, and the aperture is with thermistor diameter unanimity.
5. supersonic gas fluid measurement device according to claim 1, it is characterized in that: the main body of expelling plate, dash receiver is a circular circuit board, diameter is consistent with the through-hole diameter of urceolus both sides, the plate upper edge is slightly less than the circumference of acoustic(al)absorbent external diameter, be evenly distributed with several small through hole, be close to circular circuit board center welding ultrasonic emitting head and receive head, receive thermistor of head next door welding, welding and assembling height is controlled at half of acoustic(al)absorbent length, and four metal needles are welded at the back side again; Thermistor of center, emitting head back side welding, welding and assembling height is half of air inlet height of baffle plate, four metal needles are welded on the next door again, and two groups of metal needles receive head, thermistor electrical connection with ultrasonic emitting head, ultrasound wave respectively by circular circuit board Copper Foil cabling.
6. supersonic gas fluid measurement device according to claim 1, it is characterized in that: the air inlet baffle plate is identical with the baffle arrangement of giving vent to anger, adopt engineering plastics, its axis has a through hole, the first half be can the overcoat tracheae valve, Lower Half is the circular bottom plate that diameter equals urceolus both sides through-hole diameter, even four apertures that distribute of straight line above the base plate, pitch-row equals four pin metal stitch spacings, and the aperture is slightly larger than the metal needle diameter, allows metal needle to pass aperture.
7. supersonic gas fluid measurement device according to claim 4, it is characterized in that: acoustic(al)absorbent is installed in urceolus central through hole inside, radiating circuit plate and circuit board for receiving are installed in both sides, ultrasonic emitting head and reception head just in time extend into acoustic(al)absorbent central through hole the inside, and the thermistor on the circuit board for receiving just in time extend into the eccentric small through hole of acoustic(al)absorbent centre position, and the thermistor on the radiating circuit plate just in time extend into the through hole centre position of air inlet baffle plate.
8. according to claim 5 or 6 described supersonic gas fluid measurement devices, it is characterized in that: expelling plate and dash receiver both sides are installed O type rubber ring respectively, the air inlet baffle plate, the baffle plate of giving vent to anger, circlip, and metal needle passes the air inlet baffle plate and the aperture on the plate baffle plate of giving vent to anger after curved 90 degree angles, circlip is stuck in the circlip groove of outer tube inner wall, can keep off and compress into the gas baffle plate and the baffle plate of giving vent to anger, and then compression O type rubber ring, rely on O type rubber ring elastic force that expelling plate, dash receiver are squeezed on the ring-shaped platform of urceolus inside, and metal needle is welded on the main control board.
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| Application Number | Priority Date | Filing Date | Title |
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| CNU2008200635194U CN201222055Y (en) | 2008-05-27 | 2008-05-27 | Apparatus for measuring ultrasonic gas concentration |
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| Application Number | Priority Date | Filing Date | Title |
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| CNU2008200635194U CN201222055Y (en) | 2008-05-27 | 2008-05-27 | Apparatus for measuring ultrasonic gas concentration |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104483380A (en) * | 2014-12-19 | 2015-04-01 | 郑州光力科技股份有限公司 | Temperature-compensation-based ultrasonic wave gas concentration measurement method and temperature-compensation-based ultrasonic wave gas concentration measurement device |
| CN107064295A (en) * | 2017-01-14 | 2017-08-18 | 西安科技大学 | A kind of methane gas concentration measurement system and method |
| CN107064293A (en) * | 2017-06-03 | 2017-08-18 | 常州顺创电气科技有限公司 | SF6 detectors and detection method, compensation method and method of work |
| CN107923880A (en) * | 2015-07-03 | 2018-04-17 | 卡姆鲁普股份有限公司 | Turbidity transducer based on ultrasonic measurement |
| CN108037189A (en) * | 2017-12-06 | 2018-05-15 | 李伟 | A kind of ultrasound diffusion type Western medicine content detection device |
-
2008
- 2008-05-27 CN CNU2008200635194U patent/CN201222055Y/en not_active Expired - Fee Related
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104483380A (en) * | 2014-12-19 | 2015-04-01 | 郑州光力科技股份有限公司 | Temperature-compensation-based ultrasonic wave gas concentration measurement method and temperature-compensation-based ultrasonic wave gas concentration measurement device |
| CN107923880A (en) * | 2015-07-03 | 2018-04-17 | 卡姆鲁普股份有限公司 | Turbidity transducer based on ultrasonic measurement |
| CN107923880B (en) * | 2015-07-03 | 2020-09-08 | 卡姆鲁普股份有限公司 | Turbidity sensor based on ultrasonic measurement |
| US11391699B2 (en) | 2015-07-03 | 2022-07-19 | Kamstrup A/S | Turbidity sensor based on ultrasound measurements |
| CN107064295A (en) * | 2017-01-14 | 2017-08-18 | 西安科技大学 | A kind of methane gas concentration measurement system and method |
| CN107064295B (en) * | 2017-01-14 | 2019-07-02 | 西安科技大学 | A kind of methane gas concentration measurement system and method |
| CN107064293A (en) * | 2017-06-03 | 2017-08-18 | 常州顺创电气科技有限公司 | SF6 detectors and detection method, compensation method and method of work |
| CN108037189A (en) * | 2017-12-06 | 2018-05-15 | 李伟 | A kind of ultrasound diffusion type Western medicine content detection device |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20090415 Termination date: 20100527 |